Hello- I have been dealing with this issue for several years, and would like to figure out a way to solve it once and for all. The rear wheels on my 2005 Sentra are not aligned properly, and there is no adjustment possible. Drivers side is toed in and passenger side is toed out, the most significant issue being the passenger side. Even with tire rotations, I wear the inside of the right rear enough to require replacement in 25K miles. I have had the car to alignment shops from Virginia to California, and they all find the problem and they all tell me there is no adjustment (which I know to be true). I have received recommendations including 1) just keep putting tires on it; 2) replace the entire rear assembly; 3)take it to a frame machine and let them try to bend it.
I have not had much luck finding anyone that has taken the frame machine approach. The rear is not a straight axle, but a torsion beam assembly. I am not sure bending on that is advisable, or will yield the desired results. So I come to the community for some comments and advice. Thanks.
The rear beam is mounted via some rubber bushings. If you have a bad bushing, it could cause the beam to be out of alignment.
Take a tape measure and measure from the center of the front wheel to the center of the rear wheel on each side to make sure they are the same. If not, thats a sign of a bad bushing.
When one side of the rear is toed in and the other toed out, that is a sign that the beam is not properly located, not a sign of a bent beam.
Maybe that “little old lady” whacked a curb with it? I think @keith may be right. If axle got curbed it may be shifted back on one side. The mountings could have been bent a bit. If a mechanic loosens up the trailing arms and it might be shifted back into place. The bolt holes may have to filed out a little oval to get it back to the correct spot.
If the beam axle is bent, the tapered shims are the way to go.
My bet is that the car was in an accident and the unibody was whomped out of shape.
A body shop with an alignment table could confirm this… but if I’m right it might be impossible to repair without serious investment.
Cannot use shims, the spindle is welded not bolted on.
Regarding the beam being shifted, i asked one of the alignment shops to consider this, but didn’t get any serious feedback. At the next alignment I will be more aggressive about checking. I also need to further investigate possible beam replacement. Someone mentioned here a replacement beam may be around $450. I have had two shops tell me it would cost $900-$1000 to replace it and they both were planning to use a used part, not new. So I need to research the true cost of the part(s).
Thanks for all the discussion here.
Another test you can do is to have someone else drive your car while you follow it in another vehicle to see if the car is “crabbing” or “dogwalking”. This is where the car isn’t pointing exactly in the direction that it is going in, like an airplane landing in a crosswind. That is most often caused by the axle shifting from its original location.
If it is tracking true, then the alignment shop was wrong and their equipment needs to be calibrated, as is often the case.